The present invention relates generally to brake-controlling devices used for such vehicles as trucks, and more particularly, to a safety-brake control system for automatically actuating the parking-brake valve in response to a predetermined operator movement.
Most motorized land vehicles have brake systems which are fluid operated, either by air or liquid, and which are normally controlled by a foot pedal. Usually, the vehicle is also equipped with a hand-operated parking brake valve which, as a desirable safety practice, should be actuated to set the parking brake whenever the operator leaves the vehicle. There are many times, however, when the operator forgets to effect the setting of the parking brake. The consequences of this inadvertence can be costly in damaged property and more importantly, tragic, if a person is injured should the vehicle move uncontrollably in the absence of the operator.
Automatic brake-setting systems have been developed and for the most part, adequately fulfill the objectives for which they are designed. These prior art systems, however, are relatively expensive and require that substantial modifications be made to the original equipment of the vehicle to accommodate their installation. In fact, many automatic brake setting systems can only be installed on vehicles as original equipment.
Many vehicles, however, have been manufactured without automatic parking-brake system, but with manually actuatable parking-brake systems. There is a need, therefore, for a low-cost, effective safety-brake control system which can be easily incorporated into a conventional parking-brake system on a land vehicle.
It is the general object of the present invention, therefore, to provide an improved safety-brake control system for automatically actuating the parking brakes in response to a specific operator action.